Some Questions

So, as I pursue my research into radio I have a few preliminary questions that some of you might be able to answer...

What is the average cost to run a typical commercial radio station?
What about LPFM stations?
College radio stations?
Is there a text or source that could answer questions like these?

What is the basic minimum of equipment needed for an LPFM station to broadcast?
Approximately what would it cost?

What about radio in an emergency?
Could a radio station be run by a generator in a disaster?

Has the FCC stopped issuing LPFM licenses? If so, why?